Puppeteer | Wait for all JavaScript is executed

I try to take screenshots from multiple pages, which should be fully loaded (including lazy loaded images) for later comparison.

I found the lazyimages_without_scroll_events.js example which helps a lot.

With the following code the screenshots looking fine, but there is some major issue.

async function takeScreenshot(browser, viewport, route) {
  return browser.newPage().then(async (page) => {
    const fileName = `${viewport.directory}/${getFilename(route)}`;

    await page.setViewport({
      width: viewport.width,
      height: 500,
    });
    await page.goto(
        `${config.server.master}${route}.html`,
        {
          waitUntil: 'networkidle0',
        }
    );
    await page.evaluate(() => {
      /* global document,requestAnimationFrame */
      let lastScrollTop = document.scrollingElement.scrollTop;

      // Scroll to bottom of page until we can't scroll anymore.
      const scroll = () => {
        document.scrollingElement.scrollTop += 100;
        if (document.scrollingElement.scrollTop !== lastScrollTop) {
          lastScrollTop = document.scrollingElement.scrollTop;
          requestAnimationFrame(scroll);
        }
      };
      scroll();
    });
    await page.waitFor(5000);
    await page.screenshot({
      path: `screenshots/master/${fileName}.png`,
      fullPage: true,
    });

    await page.close();
    console.log(`Viewport "${viewport.name}", Route "${route}"`);
  });
}

Issue: Even with higher values for page.waitFor() (timeout), sometimes not the all of the frontend related JavaScripts on the pages were fully executed.

For some older pages where some JavaScript could change the frontend. F.e. in one legacy case a jQuery.matchHeight.

Best case: In an ideal world Puppeteer would wait till all JavaScript is evaluated and executed. Is something like this possible?